1. Field of the Invention
The present invention relates to an interior shock absorbing structure for a vehicle, provided with shock absorbing member disposed on a surface of a reinforcing beam, such as a roof brace for reinforcing a roof panel, on the side of a passenger room to protect passengers.
2. Description of the Prior Art
Generally, a roof panel 1 of a vehicle body is provided on its inner surface facing a passenger room with roof braces 3, i.e., lateral reinforcing beams, as shown in FIG. 3. The roof panel 1 is long if the vehicle is a one-box vehicle, and the long roof panel 1 is provided with a plurality of the roof braces 3 arranged at proper longitudinal intervals.
Generally, the surface of the roof brace 3 facing the passenger room is covered with interior finishing materials called roof trim. If the passenger""s head should strike against the roof due to accidental rolling of the vehicle or bounce of the vehicle when the vehicle travels a bumpy road, there is the possibility that the passenger""s head strikes against the roof brace 3 and the passenger""s head is injured even though the roof brace 3 is covered with the roof trim.
To prevent such an accident, there has been proposed an interior shock absorbing structure having a reinforcing beam and provided on its surface facing the passenger room with a shock absorbing member as shown in FIG. 4. Such interior shock absorbing structure is disclosed in JP-A 9-123940. There has also been proposed and used a similar interior shock absorbing structure having a reinforcing beam as shown in FIG. 5.
The first mentioned known interior shock absorbing structure shown in FIG. 4 does not include a lateral roof brace. As shown in FIG. 4, the structure has a reinforcing panel 24 longitudinally extending along each side of the vehicle roof. The reinforcing panel 24 forms a roof side rail 20 together with a longitudinally extending outer panel 22. The roof side rail 20 functions as a reinforcing beam. An inner panel 26 extends longitudinally and attached to the inner side of the reinforcing panel 24 to form a space of a predetermined thickness H. The inner panel 26 has a thickness smaller than the thicknesses of the outer panel 22 and the reinforcing panel 24, so that, if the passenger""s head 32 should strike against the inner panel 26, the inner panel 26 can be easily deformed and is able to absorb shocks.
The second mentioned known interior shock absorbing structure shown in FIG. 5A has a corrugated shock absorbing member 44 extending between right and left side rails 42 on the inner side of a roof panel 1. The shock absorbing member 44 is positioned on the inner surface facing a passenger room of a roof brace 43, i.e., a lateral reinforcing beam. As shown in FIG. 5B, the shock absorbing member 44 has a corrugated shape having a trapezoidal sectional shape and a predetermined shock absorbing stroke a as shown in FIG. 5B. The upper surface of the shock absorbing member 44 is bonded to the roof brace 43.
The shock absorbing members of these known interior shock absorbing structures shown in FIGS. 4, 5A and 5B are provided on their surfaces facing the inner surfaces of the side rails and the roof braces with joining parts, such as flanges, to be fastened to the side rails and the roof braces, respectively.
Therefore, for example, in the interior shock absorbing structure shown in FIGS. 5A and 5B, a force is exerted through a roof trim 2 on the shock absorbing member 44 to deform the same in a shape as indicated by chain lines if the passenger""s head should strike against the ceiling in an accident. Accordingly, the passenger""s head will not strike directly against the roof brace 43, i.e., the reinforcing beam, and will not be seriously shocked and injury to the passenger can be limited to the least extent.
The joining parts of the shock absorbing member 44, i.e., the upper walls of ridges of the corrugated shock absorbing member 44, is joined to the lower surface of the roof brace 43 facing the passenger room,. Therefore, the shock absorbing member 44 is deformed as indicated by the chain lines when the shock absorbing member 44 absorbs shocks; that is, the side walls 44S of the ridges of the corrugated shock absorbing member 44 collapse. Accordingly, it is impossible to secure a large deformation allowance without reducing the dimensions of the passenger room and hence the shock absorbing ability of the shock absorbing member 44 is limited. The inner panel 26 shown in FIG. 4 also has the same problems.
Accordingly, it is an object of the present invention to provide an interior shock absorbing structure similar to the known interior shock absorbing structure, capable of solving the problems in the known interior shock absorbing structure and of employing a shock absorbing member attached to a reinforcing beam secured to a roof panel and having a large deformation allowance, having an enhanced shock absorbing ability to safely protect passengers.
According to the present invention. an interior shock absorbing structure for a vehicle has a shock absorbing member attached to a reinforcing beam for reinforcing a roof panel and covering a lower surface facing a passenger room of the reinforcing beam, wherein the shock absorbing member is fixed to the structure at positions nearer to the roof panel than the lower surface of the reinforcing beam.
In the interior shock absorbing structure according to the present invention, the reinforcing beam may have joining flanges, the shock absorbing member may have joining flanges, and the joining flanges of the shock absorbing member may be superposed on and joined fixedly to the joining flanges of the reinforcing beam.
The shock absorbing member may be fixedly joined to a wide bracket joined to an upper wall member on the side of the roof panel of the reinforcing beam.
Furthermore, openings for an electrode for joining the bracket to the upper wall member on the side of the roof panel may be formed in a lower wall member on the side of the passenger room of the reinforcing beam.
The shock absorbing member may be provided with punched recesses for adjusting the buckling strength of the shock absorbing member.
Furthermore, the shock absorbing member may have an inner wall facing the passenger room, and side walls extending from the opposite side edges of the inner wall and having joining parts, respectively.
Since the joining flanges of the shock absorbing member are superposed on the joining flanges of the reinforcing beam and the joining flanges are joined together, the shock absorbing member and the reinforcing beam can be assembled when forming the reinforcing beam by joining together respective joining flanges of the upper and lower wall members of the reinforcing beam, which simplifies processes for constructing the interior shock absorbing structure. Thus, the shock absorbing member can be joined to the reinforcing beam at the positions nearer to the roof panel with respect to the lower wall member of the reinforcing member.
The shock absorbing member is fixedly joined to the wide bracket joined to the upper wall member of the reinforcing beam, and the shock absorbing member is joined to the bracket at positions at a considerable distance toward the roof panel from the lower wall member of the reinforcing beam. Therefore, a long shock absorbing stroke can be obtained to exercise a high shock absorbing ability.
Furthermore, the lower wall member of the reinforcing beam is provided with the openings for receiving the spot welding electrode for spot-welding the upper wall member of the reinforcing beam the bracket, the assembly of the reinforcing beam and the shock absorbing member can be easily joined to the bracket.
The buckling strength of the shock absorbing member can be selectively determined by properly determining the size and the number of the recesses formed in the side walls of the shock absorbing member.
Thus, the present invention provides the interior shock absorbing structure similar to the known interior shock absorbing structure, employing the shock absorbing member attached to the reinforcing beam for reinforcing the roof panel and having a large deformation allowance, having an increased shock absorbing ability to safely protect passengers.
Preferred embodiments of the present invention will be understood from the following detailed description referring to the accompanying drawings.